Kuraray Co., Ltd.

Kanayo Nakada

Yoshihiro Morishita

Tomohiro Ono

Moe Kawahara

Shinya Oshita

Makoto Akai

Hiroshi Oshima

A laminate is provided which includes a substrate and a structural body including a base portion and a through hole and which can concurrently satisfy stickiness and releasability and can be released with no or little adhesive residue. The laminate includes a substrate and a structural body disposed on the surface of at least one side of the substrate, the structural body including a base portion and a through hole. The base portion of the structural body includes an acrylic triblock copolymer (I) and no tackifier resins or includes an acrylic triblock copolymer (I) and a tackifier resin in a tackifier resin/(I) mass ratio of not more than 20/100. The acrylic triblock copolymer (I) includes two polymer blocks (A1) and (A2) each including methacrylic acid ester units and one polymer block (B) including acrylic acid ester units represented by the general formula CH═CH—COOR(1) (wherein Rdenotes a C4-C12 organic group). The acrylic triblock copolymer (I) has an (A1)-(B)-(A2) block structure and a weight average molecular weight of 50,000 to 250,000. The total content of the polymer blocks (A1) and (A2) is not more than 35 mass % of the acrylic triblock copolymer (I).

Laminates having perforated structural body

A laminate production method is provided which can sufficiently prevent the occurrence of blocking without causing deterioration in the outstanding characteristics of acrylic block copolymers such as adhesive performance, and can also ensure excellent processability during extrusion. The laminate production method includes a step (1) of bringing raw pellets of an acrylic block copolymer (A) into contact with an aqueous dispersion (C) containing acrylic resin particles (B) and no surfactants, the acrylic block copolymer (A) including at least one polymer block (a1) including acrylic acid alkyl ester units and at least one polymer block (a2) including methacrylic acid alkyl ester units, a step (2) of removing water attached to the pellets and thereby obtaining pellets (D), and a step (3) of preparing an adhesive composition using an adhesive feedstock including the pellets (D) from the step (2), and extruding the adhesive composition to form an adhesive layer and thereby producing a laminate including the adhesive layer and a substrate layer.

Laminate production method

Pellets of an acrylic block copolymer (I) having a polymer block (A1) containing methacrylic acid ester units and a polymer block (B1) containing acrylic acid ester units, and an acrylic polymer (II) having 35 mass % or more methyl methacrylate units are provided. The polymer block (B1) is made of methyl acrylate units and acrylic acid ester units of formula CH═CH—COOR(1), wherein Rrepresents a C4-C12 alkyl group. A shaped article prepared with the pellets is also provided.

Pellets including block copolymer and shaped articles obtained from such pellets

The invention provides a laminating acrylic thermoplastic polymer composition which is favorably laminated together with a layer including a plasticizer-containing polymer composition while ensuring that the migration of the plasticizer into the acrylic thermoplastic polymer composition layer is small and the resultant laminate attains excellent durability, and also provides a laminate obtained by laminating a layer including the laminating acrylic thermoplastic polymer composition onto one or both sides of a layer including the plasticizer-containing polymer composition. Further, the invention provides a polymer composition which, when the plasticizer-containing polymer described above is a vinyl chloride-based polymer, can keep sufficient adhesive force after being adhered to a layer including such a vinyl chloride-based polymer, and also provides an adhesive product using the composition. The laminating acrylic thermoplastic polymer composition is a composition for lamination with a layer including a plasticizer-containing polymer composition. The acrylic thermoplastic polymer composition includes an acrylic block copolymer (I) including at least one polymer block (A) containing methacrylic acid ester units and at least one polymer block (B) containing acrylic acid ester units; and the acrylic acid ester units constituting the polymer block (B) in the acrylic block copolymer (I) include an acrylic acid ester (1) unit represented by the general formula CH&#x2550;CH&#x2014;COOR(1) (wherein Ris an organic group having 1 to 3 carbon atoms).

Laminating acrylic thermoplastic polymer compositions

Described herein is a pressure-sensitive adhesive composition containing an acrylic block copolymer (I) having a polymer block (A) containing methacrylic acid ester units and a polymer block (B) containing acrylic acid ester units which are derived from an acrylic acid ester (1) represented by the general formula CH&#x2550;CH&#x2014;COOR(1) (wherein Ris an organic group of 4 to 6 carbon atoms) and an acrylic acid ester (2) represented by the general formula CH&#x2550;CH&#x2014;COOR(2) (wherein Ris an organic group of 7 to 12 carbon atoms), the mass ratio (1)/(2) of said acrylic acid ester (1) to said acrylic acid ester (2) being 65/35 to 20/80. The tan &#x3b4; value of viscoelasticity of the acrylic block copolymer (I), as measured at a frequency of 1 Hz, is 1&#xd7;10to 1&#xd7;10in the range of 50 to 100&#xb0; C.

Acrylic pressure-sensitive adhesive composition and pressure-sensitive adhesive products

[Object] To provide an acrylic block copolymer which can be used in an adhesive composition to give an excellent adhesive force, cohesive force, holding power, tack, and hot-melt coatability; and also to provide an adhesive composition containing such a block copolymer. [Solution] An acrylic block copolymer (I) contains at least two polymer blocks (A) containing methacrylic acid ester units and at least one polymer block (B) containing acrylic acid ester units, wherein the acrylic block copolymer (I) has structure of blocks (A)-(B)-(A), a weight average molecular weight (Mw) ranging from 30,000 to 100,000 and a melt viscosity of not more than 100,000 mPa&#xb7;s, the melt viscosity being measured at 100&#xb0; C. with a Brookfield viscometer.

Acrylic block copolymer and adhesive composition

Provided are an adhesive composition suitable for a hot-melt adhesive which has a low tack and which after adhering to an adherend and through heat treatment comes to have sufficient adhesive force; and an adhesive product using the adhesive composition. The hot-melt adhesive composition includes an acrylic block copolymer (I) having at least one polymer block (A) including methacrylic acid ester units and at least one polymer block (B) including acrylic acid ester units, wherein the acrylic acid ester units constituting the polymer block (B) contain an acrylic acid ester (1) represented by CH&#x2550;CH&#x2014;COOR(1) (wherein Ris an organic group having 1 to 3 carbon atoms) and an acrylic acid ester (2) represented by CH&#x2550;CH&#x2014;COOR(2) (wherein Ris an organic group having 4 to 12 carbon atoms), and a mass ratio (1)/(2) of the acrylic acid ester (1) to the acrylic acid ester (2) is 90/10 to 25/75.

Hot-melt adhesive composition

There are provided a pressure-sensitive adhesive composition which is excellent in durability, whitening resistance, hot-melt processability, pressure-sensitive adhesion properties, holding power at high temperatures, heat resistance, weathering resistance, compatibility with tackifying resins, low-temperature properties and transparency, is excellent also in balance of these properties and rarely suffers adhesion acceleration, and pressure-sensitive adhesive products using the pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition comprises an acrylic block copolymer (I) having a polymer block (A) comprising methacrylic acid ester units and a polymer block (B) comprising acrylic acid ester units which are derived from an acrylic acid ester (1) represented by the general formula CH&#x2550;CH&#x2014;COOR(1) (wherein Ris an organic group of 4 to 6 carbon atoms) and an acrylic acid ester (2) represented by the general formula CH&#x2550;CH&#x2014;COOR(2) (wherein Ris an organic group of 7 to 12 carbon atoms), the mass ratio (1)/(2) of said acrylic acid ester (1) to said acrylic acid ester (2) being 65/35 to 20/80.

An adhesive containing a block copolymer having at least one structure represented by formula: -[A1]-[B/A2]-, where [A1] represents a polymer block composed of a structural unit derived from a methacrylic acid ester (A1), [B/A2] represents a copolymer block composed of a structural unit derived from an acrylic acid ester (B) and a structural unit derived from a methacrylic acid ester (A2), and the copolymer block [B/A2] has a gradient copolymer block section in which a copolymerization ratio of the methacrylic acid ester (A2) continuously increases from a section connected to the polymer block [A1]. The block copolymer has a total content of the structural units derived from the methacrylic acid ester (A1) and the methacrylic acid ester (A2) of 5% to 60% by mass, a weight-average molecular weight (Mw) of 30,000 to 300,000, and a molecular weight distribution (Mw/Mn) of 1.0 to 1.5.

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Tsukuba, Japan

Kanayo Nakada